Is there anything in the Universe that is not fundamentally made up of matter?

[javisot]

I think the problem is that you aren't really asking questions about physics, just about words.

It's incredible how often this happens, ending up discussing language instead of physics.

 

[Amazed]

Somebody already posted the standard model particle list upthread. Ignore photons (the electromagnetic field), gluons (the strong force), up and down quarks (they make up protons and neutrons) and electrons. Everything else is made up of the other stuff on the list. Plus, we don't know yet what dark matter and dark energy are (if they're not just a flaw in our understanding of gravity).

I think the problem is that you aren't really asking questions about physics, just about words. Here is the Lagrangian for the standard model:View attachment 369579(from Wikipedia). This is a "Theory of Everything Except Gravity". There is no term in it for "everything" (or even "everything except gravity"). There is no term in it for "matter", although there are terms in it that describe the behaviour of everything in the standard model list posted earlier, so some subset of the terms describe whatever you choose to mean by the word.

Agreeing exactly which of the terms in that expression correspond to the word "matter" is entirely irrelevant to getting anything done - it's just stamp collecting, as Rutherford once said. If we believe we know which of the terms are relevant to an experiment we can calculate the behaviour of the experiment and compare our prediction to the reality. If it matches, great. If it doesn't (and we can't explain it as some other term we forgot to account for) then we have evidence for something new. Whether the terms we include are labelled "matter" or not changes nothing about the outcome.

(Note that most physics is not done starting with the standard model Lagrangian. It would be like trying to predict the outcome of a football match by studying the motion of every atom in the stadium at the match start. Possible in principle but absurd in practice.)

Finally, here are three examples of this thinking in practice, although in the field of gravity rather than particle physics. In the 1980s we noticed some of our space probes weren't quite where we predicted them to be. That turned out to be something we forgot to account for - a small rocket effect due to an interaction between the crafts' radiothermal generators and their antenna. In the 1840s we noticed that some of the outer planets weren't quite where we predicted them to be. That turned out to be something we didn't know to account for - Neptune, then undiscovered. In the 1890s we noticed that Mercury wasn't quite where we predicted it to be. That turned out to be that our theory of gravity was wrong, and was explained by General Relativity.

Notice that none of this hinges on arguments about names - it's all quantitative prediction and testing. Our problem at the moment is that we know our theories aren't completely correct, but we have never been able to generate a situation where they make detectably incorrect predictions. So we have little leverage in trying to develop better theories.

As long as there is a realisation that your theories are not completely correct, then all is well and good.

Words are used in theories, and words are denoted by symbols. Every symbol in equations is known and understood by words alone. So, if, and when, we just find the correct and right words, then developing far more correct and better theories can begin again.

 

[Amazed]

It's incredible how often this happens, ending up discussing language instead of physics.

It is not surprising how often people end up disagreeing, bickering, and even fighting over things like different interpretations, in things like physics, instead of just discussing and agreeing upon the words being used in language

 

[PeroK]

As long as there is a realisation that your theories are not completely correct, then all is well and good.

Words are used in theories, and words are denoted by symbols. Every symbol in equations is known and understood by words alone. So, if, and when, we just find the correct and right words, then developing far more correct and better theories can begin again.

There are underlying concepts in physics and mathematics that have to be understood in themselves. Words are the labels we give them so we can talk about them.

That's true beyond science. A child understands what food is before it learns the word.

 

[martinbn]

May be it is better to first study physics and then think about philosophical catogories such as matter.

 

[Ibix]

It's incredible how often this happens, ending up discussing language instead of physics.

I don't think school science or pop science do a very good job of describing the distinction between models, applications of the models, correspondence between model entities and the real world, and verification and validation of the predictions made once you've understood all that. And how that applies to literally everything, including your own mental model of everything. And how mathematical it is once you get much beyond the caveman "can I hit that rabbit with a thrown rock" level.

 

[Hill]

Even better would be to first study physics and then to realize that thinking about philosophical categories such as matter is immaterial. (Pun intended.)

 

[Ibix]

A child understands what food is before it learns the word.

I was fascinated by the fact that my child could clap three times in time to a song long before he was introduced to numbers.

 

[Dale]

Just ask me an open question, from an open perspective, for clarification.

What do you define as matter?

 

[Dale]

Why is there not a concept about 'All existing matter, space, energy considered as a whole', which plays any role in your actual physical theories?

The reason there is not a defined concept for this is because there is no measurement that depends on it. There is no “matter-ometer” that measures whether something is matter or not. So it is something that individual authors are free to define or ignore, as they find convenient.

 

[Hornbein]

There are many words that do not have a definition on which everyone agrees. I don't worry about it. I just state the definition I'm using then take it from there. Maybe in some other paper I will use some other definition for the same word.